High-voltage circuit interrupter



June 11, 1929. E. M. HEWLETT HIGH VOLTAGE CIRCUIT INTERRUPTER Filed Aug. 16, 1926 Figl.

Invenfor Edward M. HewleTT,

His Af'rorne g Patented June 11, 1929.

, UNITED, STATES EDWARD M. nEwLEr'r, or scnENEc'rnnY, NEW YoIu nssIeNon ELECTRIC COMPANY, A CORPORATION or NEW YORK.

PATENT OFFICE.

T0 G NERAL HIGH-VOLTAGE CIRCUIT INTERRUPIER.

Application filed August 16, 1926. Serial No. 129,329.

The invention relates to circuit interrupters particularly of the air brake type, and the object of the invention is to provide an unproved formof air break circuit interrupter having a magnetic arc extinguishing arrangement suitable for high voltage transmission line service.

In circuit interrupters adapted for high voltage service, such for exam le, as disconnecting switches intended or outdoor mounting, it has long been desirable to provide a magnetic blowout arrangement in order to obtain the advantages of quick minterruption of the are common in low voltage .circuit' .interrupters. However, the usual outdoor location of high voltage switch I ing apparatus, together with the-insulation difliculties encountered, render the ordinary form of magnetic blowout arrangement employed in low voltage scervice utterly unfit for interrupting high voltage circuits. In low voltage service the magnetic blowout COll ordinarily is provided with a magnetic core, as well as magnetic pole 'piecesextending into close proximity to the arc. Such an arrangement is not adapted for high voltage service, particularly in alternating current transmis sion lines due not only to the diflicult'y of suitably insulating the magnetic circuit of the blowout from the high voltage transmission lines, but also from the disturbing influence of the relatively high inductance inherentin iron core blowout coils.

My present invention provides an lmproved high voltagecircuit interrupter of a form adapted to be embodied in transmission line switching systems and having a magnetic arc blowout construction and arrangement whereby the advantages of magnetic are extinguishment maybeattained successfully .in high voltage service. In carrying out my present invention in a preferred form the high voltage circuit interrupter is constructed'with a suitable high voltage outdoor type of strain insulator interposed between the movable switch member and the stationary switch contact for maintaining the two in operative relation and at the same time providing a support for a transmission mechanically connected to the stationary switch contact. In order to provide a magnetic arc blowout for the high voltage circult interrupter, an arcing member is supported and insulated from the stationary switch contact and the circuit conductor and by means of suitable outdoor type insulators with the,

anember and is electrically connected between the arcing member and the switch contact, to-

gether with the lineconductor connected thereto, so as to be energized in series circuit with the are between the movable switch member and the arcing member Thus, it will be seen that my improved form of high voltage magnetic blowout switch is well adapted for high voltage transmission line switching service and the magnetic blowout insures a quick and eif ective suppresison of arcing upon operation of the switch.

In the accompanying drawing Fig. 1 shows diagrammatically a high voltage line disconnecting switch embodying the invention in a preferred form, and Fig. 2 shows a modification of the invention embodied in a feeder line disconnecting switch.

Referring to Fig. 1 it will be seen that the high voltage transmission line circuit interrupter comprises a pair of movable switch elements 11 and 12 which are pivotally mounted upon the ends of the support 13 secured to a suitable high voltage insulator 14. The. 'movable switch arms 11 and 12 are operated An elongateda support by the movable switch -member 11 I by means of the high voltage insulator 20,

which preferably is in the form of a plurality of interconnected insulator units, as indicated in the drawing, although other forms of high voltage insulators may be'employed if desired. The stationary switch contact 15 is mechanically connected to support the transmission line conductor L by means of the insulating elements 21, thearcing member 22 and the insulating element 23, and the sta- I tionary switch contact 15 is electrically conline circuit conductor that is electricallyand nectrd to the line conductor L by the jumper 24. The insulating elements 21 and 23, as well as the insulating member 20, are shown as ofv the high tension insulator type, and serve to anchor the line conductor L to the support 13 upon which the movable members member 11.' The coil is connected iii the.

circuit as indicated by the arrows in the draw- .ing sb asto setup a strong magnetic field 11 and 12 are mounted and, at the same time, maintain the stationary contact 15 in operating relation with the movable switch member-11 and-also the arcing member 22 in arc-- ing relation with the movable switch mem- L her 11.

In order to provide for magnetic extinguishmnt of the are in accordance with the present invention, a blowout coil 25, preterably of the elongated formfas indicated in the drawing, is located adjacent the arcing member 22 and electrically connected be.- tween the arcing member 22 and the stationary switch. contact 15, as well'as the line conductor L so that the coil 25 is energized by the current flowing in the arc between the arcing member 22 and the movable switch about the'arcing member 22 in such direction that the'arc is rapidly moved to the left along the member 22 and extended upwards therei from as indicated by the dotted lines in .the drawing. The stationary switch contact 16 likewise is mechanically connected to the support 13 on the movable switch element 12 with the highvoltage insulator 2 inter- -posed between the support and th switch contact for maintaining the latter in oper-' ative relation with the movable switch element 12. Also the line conductor L is me: chanically supported from the stationary switch element 16 throughthe strain insulator27, the arcing member 28 and the strain insulator 29, and is electrically connected to the stationary contact 16 by the jumperi3O."

; The elongated blowout coil is disposed bet viousfly described.

tween the jumper 30 and the arcing member. I 28 and electrically connectedtherebetween so,

as to set up a magnetic field about the arcing member'30 in a manner similar to that pm- From the foregoing it will be evident that 1' upon actuation of. the operating member 18 the movable switch elements 11 and 12 are operated into Y engagement with the" switch {contacts 15 and 16 to complete a circuit be tween the line conductors L and L It now the operating element 17 is operated the" switch'members 11 and 12 are returned to the offthe switch is quickly extinguished by operation of the blowout coils 25 and 30. The

are drawn between the movable switch element 1 1 and the contact 15 readily springs to the upturned end 22 ofthe arcing mem- 'ber'22 extending over the top of the, strain insulator 23 As a result the blowout coil 25' is, connected in series circuit with the are ex? tending between the arcing member 22 and the movable switch member 11. The resulti ng flow of current through the blowoutcoil 25 sets up a magnetic field that'rapidly moves openposition in which they are shown and any arcing occurring upon the opening the arc to the left along the top of the arcing member 22 until the arc becomes attenuated and breaks the circuit. Likewise, the arc spring between the movable switch element 1'2 and the upturned end 28 of the arcing member 28 is rapidly moved to the right along the arcing member and extended in the form indicated by the dotted lines until the are finally breaks. Due to the fact that the blowout coils 25, and 30 are located on opposite sides of the movable switch members, any action or the wind tending to prevent the blowing out of the arc on one of the movable switch members serves to expedite the extinguishment ofthe are from the other switch member irrespective of the direction of the wind.

The modified circuit interrupter illustrated in Fig. 2 isparticularly adapted for use as a disconnecting switch for feeder lines from an overhead high voltage transmission line. In this arrangement 'the movable switch elements 41 and 42 are pivotally mounted upon the bottom of the high voltage maintaining. thej latter in operative relation with the former. Y

The switch contacts 44 and 45 are mechanically and electrically connected to the line conductor L and the arcing members 50 and 51 are supported and insulated from the line conductor L by suitable high voltage .insulators 52 and 53.. The elongated blowout coils, similar to the form shown in Fig. 1,

are disposed between the arcing members 50 and 51 -andthe' line. conductor L as indi-' cated in the drawing, and are electrically connected to beenergiezd-by the current in P the arcs extending from the movable switch members41 and 42 to the arcing members 50 and 51 upon the opening of the switch. The respective blowoutcoils are so connected and arranged that'each is connected in' series circuit with the arc andsets up a magnetic field about the arcing member with which it is associated in such direction as to IIlQVG'tllQj are extending between the arcing member and the corresponding movable switch m'ember upward and outward as indicated in the dotted lines in the drawing.

- Upon the opening of, the switch arms '41 and 42 the cifcuit extending throughthe line conductors L and L is opened, and any arc 1 between the movable switch elements 41 and, the contact 44 immediately jumps-to the arc ing member 50. Likewise, any arcing between the movable switch element 22 and the passes through each of the arcing coils 54 and 55 and the resulting magnetic action rapidly attenuates the. arc'until it is broken.

\Vhat I claim asnew, and desire to secure by' Letters Patent of the United States, is

l. A high voltage" air break switch comprising relatively movableswit-ch elements, means for supporting at least one of said switch elements from the line conductor to be connected thereto including a high voltage tension insulator extending between the elements and secured thereto for maintaining the same in spaced operative 'relation, an arcing member mounted on insulating supports to be supported from'theline conductor to receive one end of the are from said one of said, switch elements and extending in arc? ing relation with theother of the switch elements, and an elongated air core blowout coil electrically connecting the arcing -member and the said one switch element to be included in series circuit with the arc and disposed adjacent said arcing member for magnetically I expanding the are extending between the member and the other switch element.-

2. A high voltage. air break switch comprising a movable switch member, a cooperating stationary'switch contact and a circuit con-f ductor mechanically and electrically connected thereto for supporting the same, a tension insulator for maintaining the stationary switch contact in operative relation with the movable switch member, an arcing member supported by said circult conductor and 1n= prising 'a switchmember pivotally mountsulated from said stationary switch contact and said circuit'conductor in arcing relation with the movable switch member, and an air core blowout coil disposed adjacent to said arcing member and electrically connecting the arcing member with the stationary switch contact and the circuit conductor so as to be included in series circuit with the arc.

- 3.- A high voltage air'break switch comed upon an insulating support, a cooperating stationary contact mechanically and electrically connected to a circuit conductor to be supported thereby, a strain insulator extending between the movable switch member and the stationary contact for maintaining the stationary switch contact with the circuit conductor connected thereto in operative retherefrom and the other end adjacent said cirlation with the movable switch member, an- I cuit conductor and insulated therefrom with the arcing member in arcmg relation with the movable switch member, and an elongated air core blowout c'oil disposed in substantially parallel relation with said arcing member and connected to be included inseries circuit with the are for magnetically extending the arc therealong. V

4'. A multiple break high voltage circuit interrupter comprising a pair of movable switch members mounted upon' an insulatmg sup-' port and each operable into and out of enga'gement with a cooperating stationary switch contact, an insulator extending between each of the movable switch members and the corresponding stationary switch contacts for maintaining the same in operative spaced relation, a line conductor. electrically connectedto each switch contact and arranged to be mechanically supported there-' by, an arcing member supported by and in -sulated from each stationary -switch contact and the line conductor associated therewith in cooperating relation with a corresponding one of said movable switch members, and an a1r-core blowout ,COll. disposed ad acent each arcing member and connected to be energized by the current flowing in the are between the movable switch members and the arcing members upon the opening of said switch member.

' In witness whereof, I have hereunto set my hand this 13th day of August, 1926.

EDWARD M. HEWLETT. 1 

